
export default function LibraryFactory() {
  let XcxApp = {
    WebSocket: function (url, protocol) {
      this.socketTask = wx.connectSocket({
        url: url,
        protocols: [protocol]
      })
    }
  }
  XcxApp.WebSocket.prototype.socketTask = null;
  XcxApp.WebSocket.prototype.onopen = null;
  XcxApp.WebSocket.prototype.onmessage = null;
  XcxApp.WebSocket.prototype.onclose = null;
  XcxApp.WebSocket.prototype.onerror = null;
  XcxApp.WebSocket.prototype.binaryType = "arraybuffer" //没用 就是形式上弄成一样
  XcxApp.WebSocket.prototype.init = function () {
    this.socketTask.onOpen(this.onopen)
    this.socketTask.onMessage(this.onmessage)
    this.socketTask.onClose(this.onclose)
    this.socketTask.onError(this.onerror)
  }
  XcxApp.WebSocket.prototype.send = function (data) {
    this.socketTask.send({
      data: data,
      // success: function (res) {
      //   console.log("发消息回调", res)
      // },
      // fail: function (res) {
      //   console.log("发消息回调1", res)
      // },
      // complete: function (res) {
      //   console.log("发消息回调2", res)
      // }
    })
  }
  XcxApp.WebSocket.prototype.close = function () {
    this.socketTask.close()
  }


  var PahoMQTT = (function (global) {
    var version = "@VERSION@-@BUILDLEVEL@";

    /**
     * @private
     */
    var localStorage = global.localStorage || (function () {
      var data = {};

      return {
        setItem: function (key, item) { data[key] = item; },
        getItem: function (key) { return data[key]; },
        removeItem: function (key) { delete data[key]; },
      };
    })();

    var MESSAGE_TYPE = {
      CONNECT: 1,
      CONNACK: 2,
      PUBLISH: 3,
      PUBACK: 4,
      PUBREC: 5,
      PUBREL: 6,
      PUBCOMP: 7,
      SUBSCRIBE: 8,
      SUBACK: 9,
      UNSUBSCRIBE: 10,
      UNSUBACK: 11,
      PINGREQ: 12,
      PINGRESP: 13,
      DISCONNECT: 14
    };


    var validate = function (obj, keys) {
      for (var key in obj) {
        if (obj.hasOwnProperty(key)) {
          if (keys.hasOwnProperty(key)) {
            if (typeof obj[key] !== keys[key])
              throw new Error(format(ERROR.INVALID_TYPE, [typeof obj[key], key]));
          } else {
            var errorStr = "Unknown property, " + key + ". Valid properties are:";
            for (var validKey in keys)
              if (keys.hasOwnProperty(validKey))
                errorStr = errorStr + " " + validKey;
            throw new Error(errorStr);
          }
        }
      }
    };


    var scope = function (f, scope) {
      return function () {
        return f.apply(scope, arguments);
      };
    };

    var ERROR = {
      OK: { code: 0, text: "AMQJSC0000I OK." },
      CONNECT_TIMEOUT: { code: 1, text: "AMQJSC0001E Connect timed out." },
      SUBSCRIBE_TIMEOUT: { code: 2, text: "AMQJS0002E Subscribe timed out." },
      UNSUBSCRIBE_TIMEOUT: { code: 3, text: "AMQJS0003E Unsubscribe timed out." },
      PING_TIMEOUT: { code: 4, text: "AMQJS0004E Ping timed out." },
      INTERNAL_ERROR: { code: 5, text: "AMQJS0005E Internal error. Error Message: {0}, Stack trace: {1}" },
      CONNACK_RETURNCODE: { code: 6, text: "AMQJS0006E Bad Connack return code:{0} {1}." },
      SOCKET_ERROR: { code: 7, text: "AMQJS0007E Socket error:{0}." },
      SOCKET_CLOSE: { code: 8, text: "AMQJS0008I Socket closed." },
      MALFORMED_UTF: { code: 9, text: "AMQJS0009E Malformed UTF data:{0} {1} {2}." },
      UNSUPPORTED: { code: 10, text: "AMQJS0010E {0} is not supported by this browser." },
      INVALID_STATE: { code: 11, text: "AMQJS0011E Invalid state {0}." },
      INVALID_TYPE: { code: 12, text: "AMQJS0012E Invalid type {0} for {1}." },
      INVALID_ARGUMENT: { code: 13, text: "AMQJS0013E Invalid argument {0} for {1}." },
      UNSUPPORTED_OPERATION: { code: 14, text: "AMQJS0014E Unsupported operation." },
      INVALID_STORED_DATA: { code: 15, text: "AMQJS0015E Invalid data in local storage key={0} value={1}." },
      INVALID_MQTT_MESSAGE_TYPE: { code: 16, text: "AMQJS0016E Invalid MQTT message type {0}." },
      MALFORMED_UNICODE: { code: 17, text: "AMQJS0017E Malformed Unicode string:{0} {1}." },
      BUFFER_FULL: { code: 18, text: "AMQJS0018E Message buffer is full, maximum buffer size: {0}." },
    };

    /** CONNACK RC Meaning. */
    var CONNACK_RC = {
      0: "Connection Accepted",
      1: "Connection Refused: unacceptable protocol version",
      2: "Connection Refused: identifier rejected",
      3: "Connection Refused: server unavailable",
      4: "Connection Refused: bad user name or password",
      5: "Connection Refused: not authorized"
    };


    var format = function (error, substitutions) {
      var text = error.text;
      if (substitutions) {
        var field, start;
        for (var i = 0; i < substitutions.length; i++) {
          field = "{" + i + "}";
          start = text.indexOf(field);
          if (start > 0) {
            var part1 = text.substring(0, start);
            var part2 = text.substring(start + field.length);
            text = part1 + substitutions[i] + part2;
          }
        }
      }
      return text;
    };

    //MQTT protocol and version          6    M    Q    I    s    d    p    3
    var MqttProtoIdentifierv3 = [0x00, 0x06, 0x4d, 0x51, 0x49, 0x73, 0x64, 0x70, 0x03];
    //MQTT proto/version for 311         4    M    Q    T    T    4
    var MqttProtoIdentifierv4 = [0x00, 0x04, 0x4d, 0x51, 0x54, 0x54, 0x04];


    var WireMessage = function (type, options) {
      this.type = type;
      for (var name in options) {
        if (options.hasOwnProperty(name)) {
          this[name] = options[name];
        }
      }
    };

    WireMessage.prototype.encode = function () {
      // Compute the first byte of the fixed header
      var first = ((this.type & 0x0f) << 4);


      var remLength = 0;
      var topicStrLength = [];
      var destinationNameLength = 0;
      var willMessagePayloadBytes;


      if (this.messageIdentifier !== undefined)
        remLength += 2;

      switch (this.type) {

        case MESSAGE_TYPE.CONNECT:
          switch (this.mqttVersion) {
            case 3:
              remLength += MqttProtoIdentifierv3.length + 3;
              break;
            case 4:
              remLength += MqttProtoIdentifierv4.length + 3;
              break;
          }

          remLength += UTF8Length(this.clientId) + 2;
          if (this.willMessage !== undefined) {
            remLength += UTF8Length(this.willMessage.destinationName) + 2;
            // Will message is always a string, sent as UTF-8 characters with a preceding length.
            willMessagePayloadBytes = this.willMessage.payloadBytes;
            if (!(willMessagePayloadBytes instanceof Uint8Array))
              willMessagePayloadBytes = new Uint8Array(payloadBytes);
            remLength += willMessagePayloadBytes.byteLength + 2;
          }
          if (this.userName !== undefined)
            remLength += UTF8Length(this.userName) + 2;
          if (this.password !== undefined)
            remLength += UTF8Length(this.password) + 2;
          break;

        // Subscribe, Unsubscribe can both contain topic strings
        case MESSAGE_TYPE.SUBSCRIBE:
          first |= 0x02; // Qos = 1;
          for (var i = 0; i < this.topics.length; i++) {
            topicStrLength[i] = UTF8Length(this.topics[i]);
            remLength += topicStrLength[i] + 2;
          }
          remLength += this.requestedQos.length; // 1 byte for each topic's Qos
          // QoS on Subscribe only
          break;

        case MESSAGE_TYPE.UNSUBSCRIBE:
          first |= 0x02; // Qos = 1;
          for (var i = 0; i < this.topics.length; i++) {
            topicStrLength[i] = UTF8Length(this.topics[i]);
            remLength += topicStrLength[i] + 2;
          }
          break;

        case MESSAGE_TYPE.PUBREL:
          first |= 0x02; // Qos = 1;
          break;

        case MESSAGE_TYPE.PUBLISH:
          if (this.payloadMessage.duplicate) first |= 0x08;
          first = first |= (this.payloadMessage.qos << 1);
          if (this.payloadMessage.retained) first |= 0x01;
          destinationNameLength = UTF8Length(this.payloadMessage.destinationName);
          remLength += destinationNameLength + 2;
          var payloadBytes = this.payloadMessage.payloadBytes;
          remLength += payloadBytes.byteLength;
          if (payloadBytes instanceof ArrayBuffer)
            payloadBytes = new Uint8Array(payloadBytes);
          else if (!(payloadBytes instanceof Uint8Array))
            payloadBytes = new Uint8Array(payloadBytes.buffer);
          break;

        case MESSAGE_TYPE.DISCONNECT:
          break;

        default:
          break;
      }



      var mbi = encodeMBI(remLength);  // Convert the length to MQTT MBI format
      var pos = mbi.length + 1;        // Offset of start of variable header
      var buffer = new ArrayBuffer(remLength + pos);
      var byteStream = new Uint8Array(buffer);    // view it as a sequence of bytes

      //Write the fixed header into the buffer
      byteStream[0] = first;
      byteStream.set(mbi, 1);

      // If this is a PUBLISH then the variable header starts with a topic
      if (this.type == MESSAGE_TYPE.PUBLISH)
        pos = writeString(this.payloadMessage.destinationName, destinationNameLength, byteStream, pos);
      // If this is a CONNECT then the variable header contains the protocol name/version, flags and keepalive time

      else if (this.type == MESSAGE_TYPE.CONNECT) {
        switch (this.mqttVersion) {
          case 3:
            byteStream.set(MqttProtoIdentifierv3, pos);
            pos += MqttProtoIdentifierv3.length;
            break;
          case 4:
            byteStream.set(MqttProtoIdentifierv4, pos);
            pos += MqttProtoIdentifierv4.length;
            break;
        }
        var connectFlags = 0;
        if (this.cleanSession)
          connectFlags = 0x02;
        if (this.willMessage !== undefined) {
          connectFlags |= 0x04;
          connectFlags |= (this.willMessage.qos << 3);
          if (this.willMessage.retained) {
            connectFlags |= 0x20;
          }
        }
        if (this.userName !== undefined)
          connectFlags |= 0x80;
        if (this.password !== undefined)
          connectFlags |= 0x40;
        byteStream[pos++] = connectFlags;
        pos = writeUint16(this.keepAliveInterval, byteStream, pos);
      }

      // Output the messageIdentifier - if there is one
      if (this.messageIdentifier !== undefined)
        pos = writeUint16(this.messageIdentifier, byteStream, pos);

      switch (this.type) {
        case MESSAGE_TYPE.CONNECT:
          pos = writeString(this.clientId, UTF8Length(this.clientId), byteStream, pos);
          if (this.willMessage !== undefined) {
            pos = writeString(this.willMessage.destinationName, UTF8Length(this.willMessage.destinationName), byteStream, pos);
            pos = writeUint16(willMessagePayloadBytes.byteLength, byteStream, pos);
            byteStream.set(willMessagePayloadBytes, pos);
            pos += willMessagePayloadBytes.byteLength;

          }
          if (this.userName !== undefined)
            pos = writeString(this.userName, UTF8Length(this.userName), byteStream, pos);
          if (this.password !== undefined)
            pos = writeString(this.password, UTF8Length(this.password), byteStream, pos);
          break;

        case MESSAGE_TYPE.PUBLISH:
          // PUBLISH has a text or binary payload, if text do not add a 2 byte length field, just the UTF characters.
          byteStream.set(payloadBytes, pos);

          break;

        //    	    case MESSAGE_TYPE.PUBREC:
        //    	    case MESSAGE_TYPE.PUBREL:
        //    	    case MESSAGE_TYPE.PUBCOMP:
        //    	    	break;

        case MESSAGE_TYPE.SUBSCRIBE:
          // SUBSCRIBE has a list of topic strings and request QoS
          for (var i = 0; i < this.topics.length; i++) {
            pos = writeString(this.topics[i], topicStrLength[i], byteStream, pos);
            byteStream[pos++] = this.requestedQos[i];
          }
          break;

        case MESSAGE_TYPE.UNSUBSCRIBE:
          // UNSUBSCRIBE has a list of topic strings
          for (var i = 0; i < this.topics.length; i++)
            pos = writeString(this.topics[i], topicStrLength[i], byteStream, pos);
          break;

        default:
        // Do nothing.
      }

      return buffer;
    };

    function decodeMessage(input, pos) {
      var startingPos = pos;
      var first = input[pos];
      var type = first >> 4;
      var messageInfo = first &= 0x0f;
      pos += 1;


      // Decode the remaining length (MBI format)

      var digit;
      var remLength = 0;
      var multiplier = 1;
      do {
        if (pos == input.length) {
          return [null, startingPos];
        }
        digit = input[pos++];
        remLength += ((digit & 0x7F) * multiplier);
        multiplier *= 128;
      } while ((digit & 0x80) !== 0);

      var endPos = pos + remLength;
      if (endPos > input.length) {
        return [null, startingPos];
      }

      var wireMessage = new WireMessage(type);
      switch (type) {
        case MESSAGE_TYPE.CONNACK:
          var connectAcknowledgeFlags = input[pos++];
          if (connectAcknowledgeFlags & 0x01)
            wireMessage.sessionPresent = true;
          wireMessage.returnCode = input[pos++];
          break;

        case MESSAGE_TYPE.PUBLISH:
          var qos = (messageInfo >> 1) & 0x03;

          var len = readUint16(input, pos);
          pos += 2;
          var topicName = parseUTF8(input, pos, len);
          pos += len;
          // If QoS 1 or 2 there will be a messageIdentifier
          if (qos > 0) {
            wireMessage.messageIdentifier = readUint16(input, pos);
            pos += 2;
          }

          var message = new Message(input.subarray(pos, endPos));
          if ((messageInfo & 0x01) == 0x01)
            message.retained = true;
          if ((messageInfo & 0x08) == 0x08)
            message.duplicate = true;
          message.qos = qos;
          message.destinationName = topicName;
          wireMessage.payloadMessage = message;
          break;

        case MESSAGE_TYPE.PUBACK:
        case MESSAGE_TYPE.PUBREC:
        case MESSAGE_TYPE.PUBREL:
        case MESSAGE_TYPE.PUBCOMP:
        case MESSAGE_TYPE.UNSUBACK:
          wireMessage.messageIdentifier = readUint16(input, pos);
          break;

        case MESSAGE_TYPE.SUBACK:
          wireMessage.messageIdentifier = readUint16(input, pos);
          pos += 2;
          wireMessage.returnCode = input.subarray(pos, endPos);
          break;

        default:
          break;
      }

      return [wireMessage, endPos];
    }

    function writeUint16(input, buffer, offset) {
      buffer[offset++] = input >> 8;      //MSB
      buffer[offset++] = input % 256;     //LSB
      return offset;
    }

    function writeString(input, utf8Length, buffer, offset) {
      offset = writeUint16(utf8Length, buffer, offset);
      stringToUTF8(input, buffer, offset);
      return offset + utf8Length;
    }

    function readUint16(buffer, offset) {
      return 256 * buffer[offset] + buffer[offset + 1];
    }

    /**
   * Encodes an MQTT Multi-Byte Integer
   * @private
   */
    function encodeMBI(number) {
      var output = new Array(1);
      var numBytes = 0;

      do {
        var digit = number % 128;
        number = number >> 7;
        if (number > 0) {
          digit |= 0x80;
        }
        output[numBytes++] = digit;
      } while ((number > 0) && (numBytes < 4));

      return output;
    }

    /**
   * Takes a String and calculates its length in bytes when encoded in UTF8.
   * @private
   */
    function UTF8Length(input) {
      var output = 0;
      for (var i = 0; i < input.length; i++) {
        var charCode = input.charCodeAt(i);
        if (charCode > 0x7FF) {
          // Surrogate pair means its a 4 byte character
          if (0xD800 <= charCode && charCode <= 0xDBFF) {
            i++;
            output++;
          }
          output += 3;
        }
        else if (charCode > 0x7F)
          output += 2;
        else
          output++;
      }
      return output;
    }

    /**
   * Takes a String and writes it into an array as UTF8 encoded bytes.
   * @private
   */
    function stringToUTF8(input, output, start) {
      var pos = start;
      for (var i = 0; i < input.length; i++) {
        var charCode = input.charCodeAt(i);

        // Check for a surrogate pair.
        if (0xD800 <= charCode && charCode <= 0xDBFF) {
          var lowCharCode = input.charCodeAt(++i);
          if (isNaN(lowCharCode)) {
            throw new Error(format(ERROR.MALFORMED_UNICODE, [charCode, lowCharCode]));
          }
          charCode = ((charCode - 0xD800) << 10) + (lowCharCode - 0xDC00) + 0x10000;

        }

        if (charCode <= 0x7F) {
          output[pos++] = charCode;
        } else if (charCode <= 0x7FF) {
          output[pos++] = charCode >> 6 & 0x1F | 0xC0;
          output[pos++] = charCode & 0x3F | 0x80;
        } else if (charCode <= 0xFFFF) {
          output[pos++] = charCode >> 12 & 0x0F | 0xE0;
          output[pos++] = charCode >> 6 & 0x3F | 0x80;
          output[pos++] = charCode & 0x3F | 0x80;
        } else {
          output[pos++] = charCode >> 18 & 0x07 | 0xF0;
          output[pos++] = charCode >> 12 & 0x3F | 0x80;
          output[pos++] = charCode >> 6 & 0x3F | 0x80;
          output[pos++] = charCode & 0x3F | 0x80;
        }
      }
      return output;
    }

    function parseUTF8(input, offset, length) {
      var output = "";
      var utf16;
      var pos = offset;

      while (pos < offset + length) {
        var byte1 = input[pos++];
        if (byte1 < 128)
          utf16 = byte1;
        else {
          var byte2 = input[pos++] - 128;
          if (byte2 < 0)
            throw new Error(format(ERROR.MALFORMED_UTF, [byte1.toString(16), byte2.toString(16), ""]));
          if (byte1 < 0xE0)             // 2 byte character
            utf16 = 64 * (byte1 - 0xC0) + byte2;
          else {
            var byte3 = input[pos++] - 128;
            if (byte3 < 0)
              throw new Error(format(ERROR.MALFORMED_UTF, [byte1.toString(16), byte2.toString(16), byte3.toString(16)]));
            if (byte1 < 0xF0)        // 3 byte character
              utf16 = 4096 * (byte1 - 0xE0) + 64 * byte2 + byte3;
            else {
              var byte4 = input[pos++] - 128;
              if (byte4 < 0)
                throw new Error(format(ERROR.MALFORMED_UTF, [byte1.toString(16), byte2.toString(16), byte3.toString(16), byte4.toString(16)]));
              if (byte1 < 0xF8)        // 4 byte character
                utf16 = 262144 * (byte1 - 0xF0) + 4096 * byte2 + 64 * byte3 + byte4;
              else                     // longer encodings are not supported
                throw new Error(format(ERROR.MALFORMED_UTF, [byte1.toString(16), byte2.toString(16), byte3.toString(16), byte4.toString(16)]));
            }
          }
        }

        if (utf16 > 0xFFFF)   // 4 byte character - express as a surrogate pair
        {
          utf16 -= 0x10000;
          output += String.fromCharCode(0xD800 + (utf16 >> 10)); // lead character
          utf16 = 0xDC00 + (utf16 & 0x3FF);  // trail character
        }
        output += String.fromCharCode(utf16);
      }
      return output;
    }

    /**
   * Repeat keepalive requests, monitor responses.
   * @ignore
   */
    var Pinger = function (client, keepAliveInterval) {
      this._client = client;
      this._keepAliveInterval = keepAliveInterval * 1000;
      this.isReset = false;

      var pingReq = new WireMessage(MESSAGE_TYPE.PINGREQ).encode();

      var doTimeout = function (pinger) {
        return function () {
          return doPing.apply(pinger);
        };
      };

      /** @ignore */
      var doPing = function () {
        if (!this.isReset) {
          this._client._trace("Pinger.doPing", "Timed out");
          this._client._disconnected(ERROR.PING_TIMEOUT.code, format(ERROR.PING_TIMEOUT));
        } else {
          this.isReset = false;
          this._client._trace("Pinger.doPing", "send PINGREQ");
          this._client.socket.send(pingReq);
          this.timeout = setTimeout(doTimeout(this), this._keepAliveInterval);
        }
      };

      this.reset = function () {
        this.isReset = true;
        clearTimeout(this.timeout);
        if (this._keepAliveInterval > 0)
          this.timeout = setTimeout(doTimeout(this), this._keepAliveInterval);
      };

      this.cancel = function () {
        clearTimeout(this.timeout);
      };
    };

    /**
   * Monitor request completion.
   * @ignore
   */
    var Timeout = function (client, timeoutSeconds, action, args) {
      if (!timeoutSeconds)
        timeoutSeconds = 30;

      var doTimeout = function (action, client, args) {
        return function () {
          return action.apply(client, args);
        };
      };
      this.timeout = setTimeout(doTimeout(action, client, args), timeoutSeconds * 1000);

      this.cancel = function () {
        clearTimeout(this.timeout);
      };
    };


    var ClientImpl = function (uri, host, port, path, clientId) {
      // Check dependencies are satisfied in this browser.
      if (!("WebSocket" in global && global.WebSocket !== null)) {
        throw new Error(format(ERROR.UNSUPPORTED, ["WebSocket"]));
      }
      // if (!("ArrayBuffer" in global && global.ArrayBuffer !== null)) {
      //   throw new Error(format(ERROR.UNSUPPORTED, ["ArrayBuffer"]));
      // }
      this._trace("Paho.Client", uri, host, port, path, clientId);

      this.host = host;
      this.port = port;
      this.path = path;
      this.uri = uri;
      this.clientId = clientId;
      this._wsuri = null;

      // Local storagekeys are qualified with the following string.
      // The conditional inclusion of path in the key is for backward
      // compatibility to when the path was not configurable and assumed to
      // be /mqtt
      this._localKey = host + ":" + port + (path != "/mqtt" ? ":" + path : "") + ":" + clientId + ":";

      // Create private instance-only message queue
      // Internal queue of messages to be sent, in sending order.
      this._msg_queue = [];
      this._buffered_msg_queue = [];

      // Messages we have sent and are expecting a response for, indexed by their respective message ids.
      this._sentMessages = {};

      // Messages we have received and acknowleged and are expecting a confirm message for
      // indexed by their respective message ids.
      this._receivedMessages = {};

      // Internal list of callbacks to be executed when messages
      // have been successfully sent over web socket, e.g. disconnect
      // when it doesn't have to wait for ACK, just message is dispatched.
      this._notify_msg_sent = {};

      // Unique identifier for SEND messages, incrementing
      // counter as messages are sent.
      this._message_identifier = 1;

      // Used to determine the transmission sequence of stored sent messages.
      this._sequence = 0;


      // Load the local state, if any, from the saved version, only restore state relevant to this client.
      for (var key in localStorage)
        if (key.indexOf("Sent:" + this._localKey) === 0 || key.indexOf("Received:" + this._localKey) === 0)
          this.restore(key);
    };

    // Messaging Client public instance members.
    ClientImpl.prototype.host = null;
    ClientImpl.prototype.port = null;
    ClientImpl.prototype.path = null;
    ClientImpl.prototype.uri = null;
    ClientImpl.prototype.clientId = null;

    // Messaging Client private instance members.
    ClientImpl.prototype.socket = null;
    /* true once we have received an acknowledgement to a CONNECT packet. */
    ClientImpl.prototype.connected = false;
    /* The largest message identifier allowed, may not be larger than 2**16 but
     * if set smaller reduces the maximum number of outbound messages allowed.
     */
    ClientImpl.prototype.maxMessageIdentifier = 65536;
    ClientImpl.prototype.connectOptions = null;
    ClientImpl.prototype.hostIndex = null;
    ClientImpl.prototype.onConnected = null;
    ClientImpl.prototype.onConnectionLost = null;
    ClientImpl.prototype.onMessageDelivered = null;
    ClientImpl.prototype.onMessageArrived = null;
    ClientImpl.prototype.traceFunction = null;
    ClientImpl.prototype._msg_queue = null;
    ClientImpl.prototype._buffered_msg_queue = null;
    ClientImpl.prototype._connectTimeout = null;
    /* The sendPinger monitors how long we allow before we send data to prove to the server that we are alive. */
    ClientImpl.prototype.sendPinger = null;
    /* The receivePinger monitors how long we allow before we require evidence that the server is alive. */
    ClientImpl.prototype.receivePinger = null;
    ClientImpl.prototype._reconnectInterval = 1; // Reconnect Delay, starts at 1 second
    ClientImpl.prototype._reconnecting = false;
    ClientImpl.prototype._reconnectTimeout = null;
    ClientImpl.prototype.disconnectedPublishing = false;
    ClientImpl.prototype.disconnectedBufferSize = 5000;

    ClientImpl.prototype.receiveBuffer = null;

    ClientImpl.prototype._traceBuffer = null;
    ClientImpl.prototype._MAX_TRACE_ENTRIES = 100;

    ClientImpl.prototype.connect = function (connectOptions) {
      var connectOptionsMasked = this._traceMask(connectOptions, "password");
      this._trace("Client.connect", connectOptionsMasked, this.socket, this.connected);
      if (this.connected)
        throw new Error(format(ERROR.INVALID_STATE, ["already connected"]));
      if (this.socket)
        throw new Error(format(ERROR.INVALID_STATE, ["already connected"]));

      if (this._reconnecting) {
        // connect() function is called while reconnect is in progress.
        // Terminate the auto reconnect process to use new connect options.
        this._reconnectTimeout.cancel();
        this._reconnectTimeout = null;
        this._reconnecting = false;
      }

      this.connectOptions = connectOptions;
      this._reconnectInterval = 1;
      this._reconnecting = false;
      if (connectOptions.uris) {
        this.hostIndex = 0;
        this._doConnect(connectOptions.uris[0]);
      } else {
        this._doConnect(this.uri);
      }

    };

    ClientImpl.prototype.subscribe = function (filter, subscribeOptions) {
      this._trace("Client.subscribe", filter, subscribeOptions);

      if (!this.connected)
        throw new Error(format(ERROR.INVALID_STATE, ["not connected"]));

      var wireMessage = new WireMessage(MESSAGE_TYPE.SUBSCRIBE);
      wireMessage.topics = filter.constructor === Array ? filter : [filter];
      if (subscribeOptions.qos === undefined)
        subscribeOptions.qos = 0;
      wireMessage.requestedQos = [];
      for (var i = 0; i < wireMessage.topics.length; i++)
        wireMessage.requestedQos[i] = subscribeOptions.qos;

      if (subscribeOptions.onSuccess) {
        wireMessage.onSuccess = function (grantedQos) { subscribeOptions.onSuccess({ invocationContext: subscribeOptions.invocationContext, grantedQos: grantedQos }); };
      }

      if (subscribeOptions.onFailure) {
        wireMessage.onFailure = function (errorCode) { subscribeOptions.onFailure({ invocationContext: subscribeOptions.invocationContext, errorCode: errorCode, errorMessage: format(errorCode) }); };
      }

      if (subscribeOptions.timeout) {
        wireMessage.timeOut = new Timeout(this, subscribeOptions.timeout, subscribeOptions.onFailure,
          [{
            invocationContext: subscribeOptions.invocationContext,
            errorCode: ERROR.SUBSCRIBE_TIMEOUT.code,
            errorMessage: format(ERROR.SUBSCRIBE_TIMEOUT)
          }]);
      }

      // All subscriptions return a SUBACK.
      this._requires_ack(wireMessage);
      this._schedule_message(wireMessage);
    };

    /** @ignore */
    ClientImpl.prototype.unsubscribe = function (filter, unsubscribeOptions) {
      this._trace("Client.unsubscribe", filter, unsubscribeOptions);

      if (!this.connected)
        throw new Error(format(ERROR.INVALID_STATE, ["not connected"]));

      var wireMessage = new WireMessage(MESSAGE_TYPE.UNSUBSCRIBE);
      wireMessage.topics = filter.constructor === Array ? filter : [filter];

      if (unsubscribeOptions.onSuccess) {
        wireMessage.callback = function () { unsubscribeOptions.onSuccess({ invocationContext: unsubscribeOptions.invocationContext }); };
      }
      if (unsubscribeOptions.timeout) {
        wireMessage.timeOut = new Timeout(this, unsubscribeOptions.timeout, unsubscribeOptions.onFailure,
          [{
            invocationContext: unsubscribeOptions.invocationContext,
            errorCode: ERROR.UNSUBSCRIBE_TIMEOUT.code,
            errorMessage: format(ERROR.UNSUBSCRIBE_TIMEOUT)
          }]);
      }

      // All unsubscribes return a SUBACK.
      this._requires_ack(wireMessage);
      this._schedule_message(wireMessage);
    };

    ClientImpl.prototype.send = function (message) {
      this._trace("Client.send", message);
      var wireMessage = new WireMessage(MESSAGE_TYPE.PUBLISH);
      wireMessage.payloadMessage = message;

      if (this.connected) {
        // Mark qos 1 & 2 message as "ACK required"
        // For qos 0 message, invoke onMessageDelivered callback if there is one.
        // Then schedule the message.
        if (message.qos > 0) {
          this._requires_ack(wireMessage);
        } else if (this.onMessageDelivered) {
          this._notify_msg_sent[wireMessage] = this.onMessageDelivered(wireMessage.payloadMessage);
        }
        this._schedule_message(wireMessage);
      } else {
        // Currently disconnected, will not schedule this message
        // Check if reconnecting is in progress and disconnected publish is enabled.
        if (this._reconnecting && this.disconnectedPublishing) {
          // Check the limit which include the "required ACK" messages
          var messageCount = Object.keys(this._sentMessages).length + this._buffered_msg_queue.length;
          if (messageCount > this.disconnectedBufferSize) {
            throw new Error(format(ERROR.BUFFER_FULL, [this.disconnectedBufferSize]));
          } else {
            if (message.qos > 0) {
              // Mark this message as "ACK required"
              this._requires_ack(wireMessage);
            } else {
              wireMessage.sequence = ++this._sequence;
              // Add messages in fifo order to array, by adding to start
              this._buffered_msg_queue.unshift(wireMessage);
            }
          }
        } else {
          throw new Error(format(ERROR.INVALID_STATE, ["not connected"]));
        }
      }
    };

    ClientImpl.prototype.disconnect = function () {
      this._trace("Client.disconnect");

      if (this._reconnecting) {
        // disconnect() function is called while reconnect is in progress.
        // Terminate the auto reconnect process.
        this._reconnectTimeout.cancel();
        this._reconnectTimeout = null;
        this._reconnecting = false;
      }

      if (!this.socket)
        throw new Error(format(ERROR.INVALID_STATE, ["not connecting or connected"]));

      var wireMessage = new WireMessage(MESSAGE_TYPE.DISCONNECT);


      this._notify_msg_sent[wireMessage] = scope(this._disconnected, this);

      this._schedule_message(wireMessage);
    };

    ClientImpl.prototype.getTraceLog = function () {
      if (this._traceBuffer !== null) {
        this._trace("Client.getTraceLog", new Date());
        this._trace("Client.getTraceLog in flight messages", this._sentMessages.length);
        for (var key in this._sentMessages)
          this._trace("_sentMessages ", key, this._sentMessages[key]);
        for (var key in this._receivedMessages)
          this._trace("_receivedMessages ", key, this._receivedMessages[key]);

        return this._traceBuffer;
      }
    };

    ClientImpl.prototype.startTrace = function () {
      if (this._traceBuffer === null) {
        this._traceBuffer = [];
      }
      this._trace("Client.startTrace", new Date(), version);
    };

    ClientImpl.prototype.stopTrace = function () {
      delete this._traceBuffer;
    };

    ClientImpl.prototype._doConnect = function (wsurl) {
      // When the socket is open, this client will send the CONNECT WireMessage using the saved parameters.
      if (this.connectOptions.useSSL) {
        var uriParts = wsurl.split(":");
        uriParts[0] = "wss";
        wsurl = uriParts.join(":");
      }
      this._wsuri = wsurl;
      this.connected = false;



      if (this.connectOptions.mqttVersion < 4) {
        this.socket = new global.WebSocket(wsurl, ["mqttv3.1"]);
      } else {
        this.socket = new global.WebSocket(wsurl, ["mqtt"]);
      }

      this.socket.binaryType = "arraybuffer";
      this.socket.onopen = scope(this._on_socket_open, this);
      this.socket.onmessage = scope(this._on_socket_message, this);
      this.socket.onerror = scope(this._on_socket_error, this);
      this.socket.onclose = scope(this._on_socket_close, this);
      this.socket.init()

      this.sendPinger = new Pinger(this, this.connectOptions.keepAliveInterval);
      this.receivePinger = new Pinger(this, this.connectOptions.keepAliveInterval);
      if (this._connectTimeout) {
        this._connectTimeout.cancel();
        this._connectTimeout = null;
      }
      this._connectTimeout = new Timeout(this, this.connectOptions.timeout, this._disconnected, [ERROR.CONNECT_TIMEOUT.code, format(ERROR.CONNECT_TIMEOUT)]);
    };


    ClientImpl.prototype._schedule_message = function (message) {
      // Add messages in fifo order to array, by adding to start
      this._msg_queue.unshift(message);
      // Process outstanding messages in the queue if we have an  open socket, and have received CONNACK.
      if (this.connected) {
        this._process_queue();
      }
    };

    ClientImpl.prototype.store = function (prefix, wireMessage) {
      var storedMessage = { type: wireMessage.type, messageIdentifier: wireMessage.messageIdentifier, version: 1 };

      switch (wireMessage.type) {
        case MESSAGE_TYPE.PUBLISH:
          if (wireMessage.pubRecReceived)
            storedMessage.pubRecReceived = true;

          // Convert the payload to a hex string.
          storedMessage.payloadMessage = {};
          var hex = "";
          var messageBytes = wireMessage.payloadMessage.payloadBytes;
          for (var i = 0; i < messageBytes.length; i++) {
            if (messageBytes[i] <= 0xF)
              hex = hex + "0" + messageBytes[i].toString(16);
            else
              hex = hex + messageBytes[i].toString(16);
          }
          storedMessage.payloadMessage.payloadHex = hex;

          storedMessage.payloadMessage.qos = wireMessage.payloadMessage.qos;
          storedMessage.payloadMessage.destinationName = wireMessage.payloadMessage.destinationName;
          if (wireMessage.payloadMessage.duplicate)
            storedMessage.payloadMessage.duplicate = true;
          if (wireMessage.payloadMessage.retained)
            storedMessage.payloadMessage.retained = true;

          // Add a sequence number to sent messages.
          if (prefix.indexOf("Sent:") === 0) {
            if (wireMessage.sequence === undefined)
              wireMessage.sequence = ++this._sequence;
            storedMessage.sequence = wireMessage.sequence;
          }
          break;

        default:
          throw Error(format(ERROR.INVALID_STORED_DATA, [prefix + this._localKey + wireMessage.messageIdentifier, storedMessage]));
      }
      localStorage.setItem(prefix + this._localKey + wireMessage.messageIdentifier, JSON.stringify(storedMessage));
    };

    ClientImpl.prototype.restore = function (key) {
      var value = localStorage.getItem(key);
      var storedMessage = JSON.parse(value);

      var wireMessage = new WireMessage(storedMessage.type, storedMessage);

      switch (storedMessage.type) {
        case MESSAGE_TYPE.PUBLISH:
          // Replace the payload message with a Message object.
          var hex = storedMessage.payloadMessage.payloadHex;
          var buffer = new ArrayBuffer((hex.length) / 2);
          var byteStream = new Uint8Array(buffer);
          var i = 0;
          while (hex.length >= 2) {
            var x = parseInt(hex.substring(0, 2), 16);
            hex = hex.substring(2, hex.length);
            byteStream[i++] = x;
          }
          var payloadMessage = new Message(byteStream);

          payloadMessage.qos = storedMessage.payloadMessage.qos;
          payloadMessage.destinationName = storedMessage.payloadMessage.destinationName;
          if (storedMessage.payloadMessage.duplicate)
            payloadMessage.duplicate = true;
          if (storedMessage.payloadMessage.retained)
            payloadMessage.retained = true;
          wireMessage.payloadMessage = payloadMessage;

          break;

        default:
          throw Error(format(ERROR.INVALID_STORED_DATA, [key, value]));
      }

      if (key.indexOf("Sent:" + this._localKey) === 0) {
        wireMessage.payloadMessage.duplicate = true;
        this._sentMessages[wireMessage.messageIdentifier] = wireMessage;
      } else if (key.indexOf("Received:" + this._localKey) === 0) {
        this._receivedMessages[wireMessage.messageIdentifier] = wireMessage;
      }
    };

    ClientImpl.prototype._process_queue = function () {
      var message = null;

      // Send all queued messages down socket connection
      while ((message = this._msg_queue.pop())) {
        this._socket_send(message);
        // Notify listeners that message was successfully sent
        if (this._notify_msg_sent[message]) {
          this._notify_msg_sent[message]();
          delete this._notify_msg_sent[message];
        }
      }
    };

    /**
   * Expect an ACK response for this message. Add message to the set of in progress
   * messages and set an unused identifier in this message.
   * @ignore
   */
    ClientImpl.prototype._requires_ack = function (wireMessage) {
      var messageCount = Object.keys(this._sentMessages).length;
      if (messageCount > this.maxMessageIdentifier)
        throw Error("Too many messages:" + messageCount);

      while (this._sentMessages[this._message_identifier] !== undefined) {
        this._message_identifier++;
      }
      wireMessage.messageIdentifier = this._message_identifier;
      this._sentMessages[wireMessage.messageIdentifier] = wireMessage;
      if (wireMessage.type === MESSAGE_TYPE.PUBLISH) {
        this.store("Sent:", wireMessage);
      }
      if (this._message_identifier === this.maxMessageIdentifier) {
        this._message_identifier = 1;
      }
    };

    /**
   * Called when the underlying websocket has been opened.
   * @ignore
   */
    ClientImpl.prototype._on_socket_open = function () {
      // Create the CONNECT message object.
      var wireMessage = new WireMessage(MESSAGE_TYPE.CONNECT, this.connectOptions);
      wireMessage.clientId = this.clientId;
      this._socket_send(wireMessage);
    };

    /**
   * Called when the underlying websocket has received a complete packet.
   * @ignore
   */
    ClientImpl.prototype._on_socket_message = function (event) {
      this._trace("Client._on_socket_message", event.data);
      var messages = this._deframeMessages(event.data);
      for (var i = 0; i < messages.length; i += 1) {
        this._handleMessage(messages[i]);
      }
    };

    ClientImpl.prototype._deframeMessages = function (data) {
      var byteArray = new Uint8Array(data);
      var messages = [];
      if (this.receiveBuffer) {
        var newData = new Uint8Array(this.receiveBuffer.length + byteArray.length);
        newData.set(this.receiveBuffer);
        newData.set(byteArray, this.receiveBuffer.length);
        byteArray = newData;
        delete this.receiveBuffer;
      }
      try {
        var offset = 0;
        while (offset < byteArray.length) {
          var result = decodeMessage(byteArray, offset);
          var wireMessage = result[0];
          offset = result[1];
          if (wireMessage !== null) {
            messages.push(wireMessage);
          } else {
            break;
          }
        }
        if (offset < byteArray.length) {
          this.receiveBuffer = byteArray.subarray(offset);
        }
      } catch (error) {
        var errorStack = ((error.hasOwnProperty("stack") == "undefined") ? error.stack.toString() : "No Error Stack Available");
        this._disconnected(ERROR.INTERNAL_ERROR.code, format(ERROR.INTERNAL_ERROR, [error.message, errorStack]));
        return;
      }
      return messages;
    };

    ClientImpl.prototype._handleMessage = function (wireMessage) {

      this._trace("Client._handleMessage", wireMessage);

      try {
        switch (wireMessage.type) {
          case MESSAGE_TYPE.CONNACK:
            this._connectTimeout.cancel();
            if (this._reconnectTimeout)
              this._reconnectTimeout.cancel();

            // If we have started using clean session then clear up the local state.
            if (this.connectOptions.cleanSession) {
              for (var key in this._sentMessages) {
                var sentMessage = this._sentMessages[key];
                localStorage.removeItem("Sent:" + this._localKey + sentMessage.messageIdentifier);
              }
              this._sentMessages = {};

              for (var key in this._receivedMessages) {
                var receivedMessage = this._receivedMessages[key];
                localStorage.removeItem("Received:" + this._localKey + receivedMessage.messageIdentifier);
              }
              this._receivedMessages = {};
            }
            // Client connected and ready for business.
            if (wireMessage.returnCode === 0) {

              this.connected = true;
              // Jump to the end of the list of uris and stop looking for a good host.

              if (this.connectOptions.uris)
                this.hostIndex = this.connectOptions.uris.length;

            } else {
              this._disconnected(ERROR.CONNACK_RETURNCODE.code, format(ERROR.CONNACK_RETURNCODE, [wireMessage.returnCode, CONNACK_RC[wireMessage.returnCode]]));
              break;
            }

            // Resend messages.
            var sequencedMessages = [];
            for (var msgId in this._sentMessages) {
              if (this._sentMessages.hasOwnProperty(msgId))
                sequencedMessages.push(this._sentMessages[msgId]);
            }

            // Also schedule qos 0 buffered messages if any
            if (this._buffered_msg_queue.length > 0) {
              var msg = null;
              while ((msg = this._buffered_msg_queue.pop())) {
                sequencedMessages.push(msg);
                if (this.onMessageDelivered)
                  this._notify_msg_sent[msg] = this.onMessageDelivered(msg.payloadMessage);
              }
            }

            // Sort sentMessages into the original sent order.
            var sequencedMessages = sequencedMessages.sort(function (a, b) { return a.sequence - b.sequence; });
            for (var i = 0, len = sequencedMessages.length; i < len; i++) {
              var sentMessage = sequencedMessages[i];
              if (sentMessage.type == MESSAGE_TYPE.PUBLISH && sentMessage.pubRecReceived) {
                var pubRelMessage = new WireMessage(MESSAGE_TYPE.PUBREL, { messageIdentifier: sentMessage.messageIdentifier });
                this._schedule_message(pubRelMessage);
              } else {
                this._schedule_message(sentMessage);
              }
            }

            // Execute the connectOptions.onSuccess callback if there is one.
            // Will also now return if this connection was the result of an automatic
            // reconnect and which URI was successfully connected to.
            if (this.connectOptions.onSuccess) {
              this.connectOptions.onSuccess({ invocationContext: this.connectOptions.invocationContext });
            }

            var reconnected = false;
            if (this._reconnecting) {
              reconnected = true;
              this._reconnectInterval = 1;
              this._reconnecting = false;
            }

            // Execute the onConnected callback if there is one.
            this._connected(reconnected, this._wsuri);

            // Process all queued messages now that the connection is established.
            this._process_queue();
            break;

          case MESSAGE_TYPE.PUBLISH:
            this._receivePublish(wireMessage);
            break;

          case MESSAGE_TYPE.PUBACK:
            var sentMessage = this._sentMessages[wireMessage.messageIdentifier];
            // If this is a re flow of a PUBACK after we have restarted receivedMessage will not exist.
            if (sentMessage) {
              delete this._sentMessages[wireMessage.messageIdentifier];
              localStorage.removeItem("Sent:" + this._localKey + wireMessage.messageIdentifier);
              if (this.onMessageDelivered)
                this.onMessageDelivered(sentMessage.payloadMessage);
            }
            break;

          case MESSAGE_TYPE.PUBREC:
            var sentMessage = this._sentMessages[wireMessage.messageIdentifier];
            // If this is a re flow of a PUBREC after we have restarted receivedMessage will not exist.
            if (sentMessage) {
              sentMessage.pubRecReceived = true;
              var pubRelMessage = new WireMessage(MESSAGE_TYPE.PUBREL, { messageIdentifier: wireMessage.messageIdentifier });
              this.store("Sent:", sentMessage);
              this._schedule_message(pubRelMessage);
            }
            break;

          case MESSAGE_TYPE.PUBREL:
            var receivedMessage = this._receivedMessages[wireMessage.messageIdentifier];
            localStorage.removeItem("Received:" + this._localKey + wireMessage.messageIdentifier);
            // If this is a re flow of a PUBREL after we have restarted receivedMessage will not exist.
            if (receivedMessage) {
              this._receiveMessage(receivedMessage);
              delete this._receivedMessages[wireMessage.messageIdentifier];
            }
            // Always flow PubComp, we may have previously flowed PubComp but the server lost it and restarted.
            var pubCompMessage = new WireMessage(MESSAGE_TYPE.PUBCOMP, { messageIdentifier: wireMessage.messageIdentifier });
            this._schedule_message(pubCompMessage);


            break;

          case MESSAGE_TYPE.PUBCOMP:
            var sentMessage = this._sentMessages[wireMessage.messageIdentifier];
            delete this._sentMessages[wireMessage.messageIdentifier];
            localStorage.removeItem("Sent:" + this._localKey + wireMessage.messageIdentifier);
            if (this.onMessageDelivered)
              this.onMessageDelivered(sentMessage.payloadMessage);
            break;

          case MESSAGE_TYPE.SUBACK:
            var sentMessage = this._sentMessages[wireMessage.messageIdentifier];
            if (sentMessage) {
              if (sentMessage.timeOut)
                sentMessage.timeOut.cancel();
              // This will need to be fixed when we add multiple topic support
              if (wireMessage.returnCode[0] === 0x80) {
                if (sentMessage.onFailure) {
                  sentMessage.onFailure(wireMessage.returnCode);
                }
              } else if (sentMessage.onSuccess) {
                sentMessage.onSuccess(wireMessage.returnCode);
              }
              delete this._sentMessages[wireMessage.messageIdentifier];
            }
            break;

          case MESSAGE_TYPE.UNSUBACK:
            var sentMessage = this._sentMessages[wireMessage.messageIdentifier];
            if (sentMessage) {
              if (sentMessage.timeOut)
                sentMessage.timeOut.cancel();
              if (sentMessage.callback) {
                sentMessage.callback();
              }
              delete this._sentMessages[wireMessage.messageIdentifier];
            }

            break;

          case MESSAGE_TYPE.PINGRESP:
            /* The sendPinger or receivePinger may have sent a ping, the receivePinger has already been reset. */
            this.sendPinger.reset();
            break;

          case MESSAGE_TYPE.DISCONNECT:
            // Clients do not expect to receive disconnect packets.
            this._disconnected(ERROR.INVALID_MQTT_MESSAGE_TYPE.code, format(ERROR.INVALID_MQTT_MESSAGE_TYPE, [wireMessage.type]));
            break;

          default:
            this._disconnected(ERROR.INVALID_MQTT_MESSAGE_TYPE.code, format(ERROR.INVALID_MQTT_MESSAGE_TYPE, [wireMessage.type]));
        }
      } catch (error) {
        var errorStack = ((error.hasOwnProperty("stack") == "undefined") ? error.stack.toString() : "No Error Stack Available");
        this._disconnected(ERROR.INTERNAL_ERROR.code, format(ERROR.INTERNAL_ERROR, [error.message, errorStack]));
        return;
      }
    };

    /** @ignore */
    ClientImpl.prototype._on_socket_error = function (error) {
      if (!this._reconnecting) {
        this._disconnected(ERROR.SOCKET_ERROR.code, format(ERROR.SOCKET_ERROR, [error.data]));
      }
    };

    /** @ignore */
    ClientImpl.prototype._on_socket_close = function () {
      if (!this._reconnecting) {
        this._disconnected(ERROR.SOCKET_CLOSE.code, format(ERROR.SOCKET_CLOSE));
      }
    };

    /** @ignore */
    ClientImpl.prototype._socket_send = function (wireMessage) {
      if (wireMessage.type == 1) {
        var wireMessageMasked = this._traceMask(wireMessage, "password");
        this._trace("Client._socket_send", wireMessageMasked);
      }
      else this._trace("Client._socket_send", wireMessage);

      this.socket.send(wireMessage.encode());
      /* We have proved to the server we are alive. */
      this.sendPinger.reset();
    };

    /** @ignore */
    ClientImpl.prototype._receivePublish = function (wireMessage) {
      switch (wireMessage.payloadMessage.qos) {
        case "undefined":
        case 0:
          this._receiveMessage(wireMessage);
          break;

        case 1:
          var pubAckMessage = new WireMessage(MESSAGE_TYPE.PUBACK, { messageIdentifier: wireMessage.messageIdentifier });
          this._schedule_message(pubAckMessage);
          this._receiveMessage(wireMessage);
          break;

        case 2:
          this._receivedMessages[wireMessage.messageIdentifier] = wireMessage;
          this.store("Received:", wireMessage);
          var pubRecMessage = new WireMessage(MESSAGE_TYPE.PUBREC, { messageIdentifier: wireMessage.messageIdentifier });
          this._schedule_message(pubRecMessage);

          break;

        default:
          throw Error("Invaild qos=" + wireMessage.payloadMessage.qos);
      }
    };

    /** @ignore */
    ClientImpl.prototype._receiveMessage = function (wireMessage) {
      if (this.onMessageArrived) {
        this.onMessageArrived(wireMessage.payloadMessage);
      }
    };

    ClientImpl.prototype._connected = function (reconnect, uri) {
      // Execute the onConnected callback if there is one.
      if (this.onConnected)
        this.onConnected(reconnect, uri);
    };

    ClientImpl.prototype._reconnect = function () {
      this._trace("Client._reconnect");
      if (!this.connected) {
        this._reconnecting = true;
        this.sendPinger.cancel();
        this.receivePinger.cancel();
        if (this._reconnectInterval < 128)
          this._reconnectInterval = this._reconnectInterval * 2;
        if (this.connectOptions.uris) {
          this.hostIndex = 0;
          this._doConnect(this.connectOptions.uris[0]);
        } else {
          this._doConnect(this.uri);
        }
      }
    };


    ClientImpl.prototype._disconnected = function (errorCode, errorText) {
      this._trace("Client._disconnected", errorCode, errorText);

      if (errorCode !== undefined && this._reconnecting) {
        //Continue automatic reconnect process
        this._reconnectTimeout = new Timeout(this, this._reconnectInterval, this._reconnect);
        return;
      }

      this.sendPinger.cancel();
      this.receivePinger.cancel();
      if (this._connectTimeout) {
        this._connectTimeout.cancel();
        this._connectTimeout = null;
      }

      // Clear message buffers.
      this._msg_queue = [];
      this._buffered_msg_queue = [];
      this._notify_msg_sent = {};

      if (this.socket) {
        // Cancel all socket callbacks so that they cannot be driven again by this socket.
        this.socket.onopen = null;
        this.socket.onmessage = null;
        this.socket.onerror = null;
        this.socket.onclose = null;
        if (this.socket.readyState === 1)
          this.socket.close();
        delete this.socket;
      }

      if (this.connectOptions.uris && this.hostIndex < this.connectOptions.uris.length - 1) {
        // Try the next host.
        this.hostIndex++;
        this._doConnect(this.connectOptions.uris[this.hostIndex]);
      } else {

        if (errorCode === undefined) {
          errorCode = ERROR.OK.code;
          errorText = format(ERROR.OK);
        }

        // Run any application callbacks last as they may attempt to reconnect and hence create a new socket.
        if (this.connected) {
          this.connected = false;
          // Execute the connectionLostCallback if there is one, and we were connected.
          if (this.onConnectionLost) {
            this.onConnectionLost({ errorCode: errorCode, errorMessage: errorText, reconnect: this.connectOptions.reconnect, uri: this._wsuri });
          }
          if (errorCode !== ERROR.OK.code && this.connectOptions.reconnect) {
            // Start automatic reconnect process for the very first time since last successful connect.
            this._reconnectInterval = 1;
            this._reconnect();
            return;
          }
        } else {
          // Otherwise we never had a connection, so indicate that the connect has failed.
          if (this.connectOptions.mqttVersion === 4 && this.connectOptions.mqttVersionExplicit === false) {
            this._trace("Failed to connect V4, dropping back to V3");
            this.connectOptions.mqttVersion = 3;
            if (this.connectOptions.uris) {
              this.hostIndex = 0;
              this._doConnect(this.connectOptions.uris[0]);
            } else {
              this._doConnect(this.uri);
            }
          } else if (this.connectOptions.onFailure) {
            this.connectOptions.onFailure({ invocationContext: this.connectOptions.invocationContext, errorCode: errorCode, errorMessage: errorText });
          }
        }
      }
    };

    /** @ignore */
    ClientImpl.prototype._trace = function () {
      // Pass trace message back to client's callback function
      if (this.traceFunction) {
        var args = Array.prototype.slice.call(arguments);
        for (var i in args) {
          if (typeof args[i] !== "undefined")
            args.splice(i, 1, JSON.stringify(args[i]));
        }
        var record = args.join("");
        this.traceFunction({ severity: "Debug", message: record });
      }

      if (this._traceBuffer !== null) {
        for (var i = 0, max = arguments.length; i < max; i++) {
          if (this._traceBuffer.length == this._MAX_TRACE_ENTRIES) {
            this._traceBuffer.shift();
          }
          if (i === 0) this._traceBuffer.push(arguments[i]);
          else if (typeof arguments[i] === "undefined") this._traceBuffer.push(arguments[i]);
          else this._traceBuffer.push("  " + JSON.stringify(arguments[i]));
        }
      }
    };

    /** @ignore */
    ClientImpl.prototype._traceMask = function (traceObject, masked) {
      var traceObjectMasked = {};
      for (var attr in traceObject) {
        if (traceObject.hasOwnProperty(attr)) {
          if (attr == masked)
            traceObjectMasked[attr] = "******";
          else
            traceObjectMasked[attr] = traceObject[attr];
        }
      }
      return traceObjectMasked;
    };


    var Client = function (host, port, path, clientId) {

      var uri;

      if (typeof host !== "string")
        throw new Error(format(ERROR.INVALID_TYPE, [typeof host, "host"]));

      if (arguments.length == 2) {

        clientId = port;
        uri = host;
        var match = uri.match(/^(wss?):\/\/((\[(.+)\])|([^\/]+?))(:(\d+))?(\/.*)$/);
        if (match) {
          host = match[4] || match[2];
          port = parseInt(match[7]);
          path = match[8];
        } else {
          throw new Error(format(ERROR.INVALID_ARGUMENT, [host, "host"]));
        }
      } else {
        if (arguments.length == 3) {
          clientId = path;
          path = "/mqtt";
        }
        if (typeof port !== "number" || port < 0)
          throw new Error(format(ERROR.INVALID_TYPE, [typeof port, "port"]));
        if (typeof path !== "string")
          throw new Error(format(ERROR.INVALID_TYPE, [typeof path, "path"]));

        var ipv6AddSBracket = (host.indexOf(":") !== -1 && host.slice(0, 1) !== "[" && host.slice(-1) !== "]");
        uri = "ws://" + (ipv6AddSBracket ? "[" + host + "]" : host) + ":" + port + path;
      }

      var clientIdLength = 0;
      for (var i = 0; i < clientId.length; i++) {
        var charCode = clientId.charCodeAt(i);
        if (0xD800 <= charCode && charCode <= 0xDBFF) {
          i++; // Surrogate pair.
        }
        clientIdLength++;
      }
      if (typeof clientId !== "string" || clientIdLength > 65535)
        throw new Error(format(ERROR.INVALID_ARGUMENT, [clientId, "clientId"]));

      var client = new ClientImpl(uri, host, port, path, clientId);

      //Public Properties
      Object.defineProperties(this, {
        "host": {
          get: function () { return host; },
          set: function () { throw new Error(format(ERROR.UNSUPPORTED_OPERATION)); }
        },
        "port": {
          get: function () { return port; },
          set: function () { throw new Error(format(ERROR.UNSUPPORTED_OPERATION)); }
        },
        "path": {
          get: function () { return path; },
          set: function () { throw new Error(format(ERROR.UNSUPPORTED_OPERATION)); }
        },
        "uri": {
          get: function () { return uri; },
          set: function () { throw new Error(format(ERROR.UNSUPPORTED_OPERATION)); }
        },
        "clientId": {
          get: function () { return client.clientId; },
          set: function () { throw new Error(format(ERROR.UNSUPPORTED_OPERATION)); }
        },
        "onConnected": {
          get: function () { return client.onConnected; },
          set: function (newOnConnected) {
            if (typeof newOnConnected === "function")
              client.onConnected = newOnConnected;
            else
              throw new Error(format(ERROR.INVALID_TYPE, [typeof newOnConnected, "onConnected"]));
          }
        },
        "disconnectedPublishing": {
          get: function () { return client.disconnectedPublishing; },
          set: function (newDisconnectedPublishing) {
            client.disconnectedPublishing = newDisconnectedPublishing;
          }
        },
        "disconnectedBufferSize": {
          get: function () { return client.disconnectedBufferSize; },
          set: function (newDisconnectedBufferSize) {
            client.disconnectedBufferSize = newDisconnectedBufferSize;
          }
        },
        "onConnectionLost": {
          get: function () { return client.onConnectionLost; },
          set: function (newOnConnectionLost) {
            if (typeof newOnConnectionLost === "function")
              client.onConnectionLost = newOnConnectionLost;
            else
              throw new Error(format(ERROR.INVALID_TYPE, [typeof newOnConnectionLost, "onConnectionLost"]));
          }
        },
        "onMessageDelivered": {
          get: function () { return client.onMessageDelivered; },
          set: function (newOnMessageDelivered) {
            if (typeof newOnMessageDelivered === "function")
              client.onMessageDelivered = newOnMessageDelivered;
            else
              throw new Error(format(ERROR.INVALID_TYPE, [typeof newOnMessageDelivered, "onMessageDelivered"]));
          }
        },
        "onMessageArrived": {
          get: function () { return client.onMessageArrived; },
          set: function (newOnMessageArrived) {
            if (typeof newOnMessageArrived === "function")
              client.onMessageArrived = newOnMessageArrived;
            else
              throw new Error(format(ERROR.INVALID_TYPE, [typeof newOnMessageArrived, "onMessageArrived"]));
          }
        },
        "trace": {
          get: function () { return client.traceFunction; },
          set: function (trace) {
            if (typeof trace === "function") {
              client.traceFunction = trace;
            } else {
              throw new Error(format(ERROR.INVALID_TYPE, [typeof trace, "onTrace"]));
            }
          }
        },
      });


      this.connect = function (connectOptions) {
        connectOptions = connectOptions || {};
        validate(connectOptions, {
          timeout: "number",
          userName: "string",
          password: "string",
          willMessage: "object",
          keepAliveInterval: "number",
          cleanSession: "boolean",
          useSSL: "boolean",
          invocationContext: "object",
          onSuccess: "function",
          onFailure: "function",
          hosts: "object",
          ports: "object",
          reconnect: "boolean",
          mqttVersion: "number",
          mqttVersionExplicit: "boolean",
          uris: "object"
        });

        if (connectOptions.keepAliveInterval === undefined)
          connectOptions.keepAliveInterval = 60;

        if (connectOptions.mqttVersion > 4 || connectOptions.mqttVersion < 3) {
          throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.mqttVersion, "connectOptions.mqttVersion"]));
        }

        if (connectOptions.mqttVersion === undefined) {
          connectOptions.mqttVersionExplicit = false;
          connectOptions.mqttVersion = 4;
        } else {
          connectOptions.mqttVersionExplicit = true;
        }

        if (connectOptions.password !== undefined && connectOptions.userName === undefined)
          throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.password, "connectOptions.password"]));

        if (connectOptions.willMessage) {
          if (!(connectOptions.willMessage instanceof Message))
            throw new Error(format(ERROR.INVALID_TYPE, [connectOptions.willMessage, "connectOptions.willMessage"]));
          connectOptions.willMessage.stringPayload = null;

          if (typeof connectOptions.willMessage.destinationName === "undefined")
            throw new Error(format(ERROR.INVALID_TYPE, [typeof connectOptions.willMessage.destinationName, "connectOptions.willMessage.destinationName"]));
        }
        if (typeof connectOptions.cleanSession === "undefined")
          connectOptions.cleanSession = true;
        if (connectOptions.hosts) {

          if (!(connectOptions.hosts instanceof Array))
            throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.hosts, "connectOptions.hosts"]));
          if (connectOptions.hosts.length < 1)
            throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.hosts, "connectOptions.hosts"]));

          var usingURIs = false;
          for (var i = 0; i < connectOptions.hosts.length; i++) {
            if (typeof connectOptions.hosts[i] !== "string")
              throw new Error(format(ERROR.INVALID_TYPE, [typeof connectOptions.hosts[i], "connectOptions.hosts[" + i + "]"]));
            if (/^(wss?):\/\/((\[(.+)\])|([^\/]+?))(:(\d+))?(\/.*)$/.test(connectOptions.hosts[i])) {
              if (i === 0) {
                usingURIs = true;
              } else if (!usingURIs) {
                throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.hosts[i], "connectOptions.hosts[" + i + "]"]));
              }
            } else if (usingURIs) {
              throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.hosts[i], "connectOptions.hosts[" + i + "]"]));
            }
          }

          if (!usingURIs) {
            if (!connectOptions.ports)
              throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.ports, "connectOptions.ports"]));
            if (!(connectOptions.ports instanceof Array))
              throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.ports, "connectOptions.ports"]));
            if (connectOptions.hosts.length !== connectOptions.ports.length)
              throw new Error(format(ERROR.INVALID_ARGUMENT, [connectOptions.ports, "connectOptions.ports"]));

            connectOptions.uris = [];

            for (var i = 0; i < connectOptions.hosts.length; i++) {
              if (typeof connectOptions.ports[i] !== "number" || connectOptions.ports[i] < 0)
                throw new Error(format(ERROR.INVALID_TYPE, [typeof connectOptions.ports[i], "connectOptions.ports[" + i + "]"]));
              var host = connectOptions.hosts[i];
              var port = connectOptions.ports[i];

              var ipv6 = (host.indexOf(":") !== -1);
              uri = "ws://" + (ipv6 ? "[" + host + "]" : host) + ":" + port + path;
              connectOptions.uris.push(uri);
            }
          } else {
            connectOptions.uris = connectOptions.hosts;
          }
        }

        client.connect(connectOptions);
      };


      this.subscribe = function (filter, subscribeOptions) {
        if (typeof filter !== "string" && filter.constructor !== Array)
          throw new Error("Invalid argument:" + filter);
        subscribeOptions = subscribeOptions || {};
        validate(subscribeOptions, {
          qos: "number",
          invocationContext: "object",
          onSuccess: "function",
          onFailure: "function",
          timeout: "number"
        });
        if (subscribeOptions.timeout && !subscribeOptions.onFailure)
          throw new Error("subscribeOptions.timeout specified with no onFailure callback.");
        if (typeof subscribeOptions.qos !== "undefined" && !(subscribeOptions.qos === 0 || subscribeOptions.qos === 1 || subscribeOptions.qos === 2))
          throw new Error(format(ERROR.INVALID_ARGUMENT, [subscribeOptions.qos, "subscribeOptions.qos"]));
        client.subscribe(filter, subscribeOptions);
      };


      this.unsubscribe = function (filter, unsubscribeOptions) {
        if (typeof filter !== "string" && filter.constructor !== Array)
          throw new Error("Invalid argument:" + filter);
        unsubscribeOptions = unsubscribeOptions || {};
        validate(unsubscribeOptions, {
          invocationContext: "object",
          onSuccess: "function",
          onFailure: "function",
          timeout: "number"
        });
        if (unsubscribeOptions.timeout && !unsubscribeOptions.onFailure)
          throw new Error("unsubscribeOptions.timeout specified with no onFailure callback.");
        client.unsubscribe(filter, unsubscribeOptions);
      };


      this.send = function (topic, payload, qos, retained) {
        var message;
        if (arguments.length === 0) {
          throw new Error("Invalid argument." + "length");

        } else if (arguments.length == 1) {

          if (!(topic instanceof Message) && (typeof topic !== "string"))
            throw new Error("Invalid argument:" + typeof topic);

          message = topic;
          if (typeof message.destinationName === "undefined")
            throw new Error(format(ERROR.INVALID_ARGUMENT, [message.destinationName, "Message.destinationName"]));
          client.send(message);

        } else {

          message = new Message(payload);
          message.destinationName = topic;
          if (arguments.length >= 3)
            message.qos = qos;
          if (arguments.length >= 4)
            message.retained = retained;
          client.send(message);
        }
      };


      this.publish = function (topic, payload, qos, retained) {
        var message;

        if (arguments.length === 0) {
          throw new Error("Invalid argument." + "length");

        } else if (arguments.length == 1) {

          if (!(topic instanceof Message) && (typeof topic !== "string"))
            throw new Error("Invalid argument:" + typeof topic);

          message = topic;
          if (typeof message.destinationName === "undefined")
            throw new Error(format(ERROR.INVALID_ARGUMENT, [message.destinationName, "Message.destinationName"]));
          client.send(message);

        } else {
          //parameter checking in Message object
          message = new Message(payload);
          message.destinationName = topic;
          if (arguments.length >= 3)
            message.qos = qos;
          if (arguments.length >= 4)
            message.retained = retained;
          client.send(message);
        }
      };


      this.disconnect = function () {
        client.disconnect();
      };

      this.getTraceLog = function () {
        return client.getTraceLog();
      };

      this.startTrace = function () {
        client.startTrace();
      };


      this.stopTrace = function () {
        client.stopTrace();
      };

      this.isConnected = function () {
        return client.connected;
      };
    };

    var Message = function (newPayload) {
      var payload;
      if (typeof newPayload === "string" ||
        newPayload instanceof ArrayBuffer ||
        (ArrayBuffer.isView(newPayload) && !(newPayload instanceof DataView))
      ) {
        payload = newPayload;
      } else {
        throw (format(ERROR.INVALID_ARGUMENT, [newPayload, "newPayload"]));
      }

      var destinationName;
      var qos = 0;
      var retained = false;
      var duplicate = false;

      Object.defineProperties(this, {
        "payloadString": {
          enumerable: true,
          get: function () {
            if (typeof payload === "string")
              return payload;
            else
              return parseUTF8(payload, 0, payload.length);
          }
        },
        "payloadBytes": {
          enumerable: true,
          get: function () {
            if (typeof payload === "string") {
              var buffer = new ArrayBuffer(UTF8Length(payload));
              var byteStream = new Uint8Array(buffer);
              stringToUTF8(payload, byteStream, 0);

              return byteStream;
            } else {
              return payload;
            }
          }
        },
        "destinationName": {
          enumerable: true,
          get: function () { return destinationName; },
          set: function (newDestinationName) {
            if (typeof newDestinationName === "string")
              destinationName = newDestinationName;
            else
              throw new Error(format(ERROR.INVALID_ARGUMENT, [newDestinationName, "newDestinationName"]));
          }
        },
        "qos": {
          enumerable: true,
          get: function () { return qos; },
          set: function (newQos) {
            if (newQos === 0 || newQos === 1 || newQos === 2)
              qos = newQos;
            else
              throw new Error("Invalid argument:" + newQos);
          }
        },
        "retained": {
          enumerable: true,
          get: function () { return retained; },
          set: function (newRetained) {
            if (typeof newRetained === "boolean")
              retained = newRetained;
            else
              throw new Error(format(ERROR.INVALID_ARGUMENT, [newRetained, "newRetained"]));
          }
        },
        "topic": {
          enumerable: true,
          get: function () { return destinationName; },
          set: function (newTopic) { destinationName = newTopic; }
        },
        "duplicate": {
          enumerable: true,
          get: function () { return duplicate; },
          set: function (newDuplicate) { duplicate = newDuplicate; }
        }
      });
    };

    return {
      Client: Client,
      Message: Message
    };

  })(XcxApp);
  return PahoMQTT;
};